Alternating-current lifting magnet



April 8, 1924; 1,489,284

- J. F. STEININGER ALTERNATING- CURRENT LIFTING MAGNET Filed June 18. 1923 I Patented Apr. 8, 1924.

PATENT OFFICE."

JAMES F. STEININGEB, OF CHICAGO,'ILLINOIS.

ALTERNATING-CUBRENT LIFTING MAG-NET.

Application fled June 18, 1923. Serial No. 646,275.

To all whom it may concem:

Be it known that I, JAMES F. STEIN- INoEn, a citizen of the United States of erlca, residing at Chica o, in the county I of Cookand State of Illino1s, have invented a certain new and useful Improvement in Alternating-Current Lifting Magnets, of which the following is a specification.

, This invention relates to the hand implelfl ment type of alternating current lifting and nets used in the separaholding electro-ma tion of magnetic from non-magnetic scrap metal and the like, and has for its object To provide a structural formation of the II enclosing housing of an alternating current electro-magnet of the above described type, whereby undue heating of such housing by eddy currents generated or induced thereln during continued actual use, is prevented in a simple and effective manner, all as will hereinafter more fully a pear. In the accompanying rawinga Fig. 1, is a longitudinal sectional elevation of a portable electro-magnet, embodying the present improvement.

Fig. 2, is a transverse sectional elevation on line 2.2. Fig. 1 of the same.

Fig. 3, is a bottom view of the same.

Like reference numerals indicate like parts in the different views.

As represented in the drawing, the housing 1 which forms an enclosure for the laminated core 2, windings 3, and accessories is of an approximately rectangular shell shape, from "the side walls of which extend a pair of opposed cheek plates 4: between the a hand grip 5 is attached 'free ends of which for convenience in handling the implement.

One of said check plates 4 carrying a switch 40 casin 6, in which the switch mechanism! by w ich current is conducted to the coils or windings 3, is controlled bya finger of the operator, as usualrin the present class of hand implements.

The laminated core.2, is of the usual approximately U form, with the parallel portions or legs thereof surrounded by the coils or windings 3, and with the free ends of said legs extending through anda. distance beyond the bottom wall of the housing 1 and in. proper spaced relation to constltute projecting pole pieces adapted for insertion and movement through the metal scrap or Letters. Patent, is

' hozzsmg, and coils surrounding the le likematerial to be sorted into magnetic and non-magnetic portions,

A tubular inlet neck 8 is arranged at one side of the housing 1 for the passage of the usual cable conductor 9 by which electromotive force is supplied to the windings 3 and switch mechanism 7 aforesaid.

The material part of the present improvement; in connection with the above described construction of alternating current electromagnets, consists in the provision of a space, gap or opening 10, in the bottom wall of the enclosing housing 1, extending from one parallel member or leg to the other member or legof the laminated core 2, and preferabl at the mid-width of the same, as shown in igs. 2 and 3.

Extended practical experiments have proven that the above described provision of the gap 10 acts to very effectively prevent the free flow of eddy and like currents induced in the metal of the housing 1, and the overheating of the same due to such free flow of said currents Having thus fully described my invention, what I claim as new and desire to secure by 80 1. In an alternating current electro-mag- A not, an enclosing casing of metal, a laminated core of an approximately U'form arranged in said housin Withthe-ireeends of itslegs projecting' tirou h a will of the housing, and coils surroun ing the legs of said core, the wall of the housing having a I gap extending from core leg to core leg.

2. In an alternatin current electro-mag net, an enclosing casmgof'metal, a laminated core of an approximately U form arfrom. core leg to core leg.

3. In an alternatin current electro-m net, an enclosing casing of metal, a lam f nated core of an approximately U form arranged in said housin with the free ends of its legs projecting t rougha wall of th;

0 said core, the wall of the housing havinga gap-extending from core leg to core leg at the midwidth of the same.

0's I wall of the housing having a gap extending 4. In an alternating current electromagnet, an enclosing casing of metal, a laminated core of an approximately U form arranged in said housing with the free ends of its legs projecting through a wall of the housin and a distance beyond the same, and coils surrounding the legs of said core,

the wall of the housing having a gap extending from core leg to core leg at the midwidth of the same. I 1 Signed at Chicago, Illinois, this 14th day of June, 1923'.

JAMES F. STEININGER. 

